Thread by @angryhacademic

Cardiovascular Deconditioning (20 Hours Bedrest with -5° Head-Down Tilt (HDT)) in Middle-Aged Healthy Men
sci-hub.se/10.1016/0002-9…
authors suggest during HDT MAIN cause of deconditioning is "an altered distribution of body fluids & intravascular pressures" & shift of fluid to head

this is potentially VERY important for #POTS: it suggests that our dysregulated body water regulation can be a primary source of deconditioning-like cardiovascular issues.

this means: fix the haemostasis problems to improve cardiovascular condition

#MedTwitter

this study was in a very different context to POTS so we can't read too much into it. HDT shifts fluid to the head which is the opposite to POTS. this does trigger a reduction in blood volume, reduction in oxygen consumption, low renin, tachycardia, etc tho, all similar to POTS

it implies that playing around with how body water is distributed can cause deconditioning responses by itself. therefore deconditioning is likely a consequence of POTS pathology.

That pathology then reduces our ability to be active, which independently causes deconditioning.

either way, the answer leads back to: TREATING POTS